shithub: git9

Download patch

ref: ea99345bda4e411479705f5bb9c0ba7f13bfe52d
parent: e362152c60172f7530715f034af59ffe61187516
author: Ori Bernstein <[email protected]>
date: Mon Jul 8 03:01:02 EDT 2019

Correctly compute the CRC when indexing packs.

--- a/git.h
+++ b/git.h
@@ -92,6 +92,8 @@
 
 	/* For indexing */
 	vlong	off;
+	vlong	len;
+	u32int	crc;
 
 	/* Everything below here gets cleared */
 	char	*all;
--- a/pack.c
+++ b/pack.c
@@ -119,6 +119,57 @@
 	}		
 }
 
+
+static u32int
+crc32(u32int crc, char *b, int nb)
+{
+	static u32int crctab[256] = {
+		0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 
+		0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 
+		0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 
+		0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 
+		0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 
+		0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 
+		0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 
+		0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 
+		0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 
+		0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 
+		0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 
+		0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 
+		0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 
+		0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 
+		0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 
+		0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 
+		0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 
+		0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 
+		0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 
+		0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 
+		0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 
+		0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 
+		0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 
+		0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 
+		0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 
+		0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 
+		0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 
+		0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 
+		0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 
+		0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 
+		0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 
+		0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 
+		0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 
+		0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 
+		0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 
+		0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 
+		0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
+	};
+	int i;
+
+	crc ^=  0xFFFFFFFF;
+	for(i = 0; i < nb; i++)
+		crc = (crc >> 8) ^ crctab[(crc ^ b[i]) & 0xFF];
+	return crc ^ 0xFFFFFFFF;
+}
+
 int
 bappend(void *p, void *src, int len)
 {
@@ -317,6 +368,7 @@
 		goto error;
 	if((n = decompress(&d, f, nil)) == -1)
 		goto error;
+	o->len = Boffset(f) - o->off;
 	if(d == nil || n != nd)
 		goto error;
 	if((b = readidxobject(f, h, flag)) == nil)
@@ -356,6 +408,7 @@
 	}
 	if((n = decompress(&d, f, nil)) == -1)
 		goto error;
+	o->len = Boffset(f) - o->off;
 	if(d == nil || n != nd)
 		goto error;
 	if(Bseek(f, p - r, 0) == -1)
@@ -414,6 +467,7 @@
 			free(b.data);
 			return -1;
 		}
+		o->len = Boffset(f) - o->off;
 		o->type = t;
 		o->all = b.data;
 		o->data = b.data + n;
@@ -862,6 +916,25 @@
 	return Bwrite(b, buf, len);
 }
 
+static u32int
+objectcrc(Biobuf *f, Object *o)
+{
+	char buf[8096];
+	int n, r;
+
+	o->crc = 0;
+	Bseek(f, o->off, 0);
+	for(n = o->len; n > 0; n -= r){
+		r = Bread(f, buf, n > sizeof(buf) ? sizeof(buf) : n);
+		if(r == -1)
+			return -1;
+		if(r == 0)
+			return 0;
+		o->crc = crc32(o->crc, buf, r);
+	}
+	return 0;
+}
+
 int
 indexpack(char *pack, char *idx, Hash ph)
 {
@@ -915,6 +988,8 @@
 				valid[i] = 1;
 				n++;
 			}
+			if(objectcrc(f, o) == -1)
+				return -1;
 		}
 		fprint(2, "\n");
 		if(n == nvalid){
@@ -946,7 +1021,7 @@
 
 	/* fuck it, pointless */
 	for(i = 0; i < nobj; i++){
-		PUTBE32(buf, 42);
+		PUTBE32(buf, objects[i]->crc);
 		hwrite(f, buf, 4, &st);
 	}